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Date: Tue, 14 Apr 2020 11:55:22 -0400
From: Rich Felker <dalias@libc.org>
To: Florian Weimer <fw@deneb.enyo.de>
Cc: musl@lists.openwall.com, Norbert Lange <nolange79@gmail.com>
Message-ID: <20200414155522.GB11469@brightrain.aerifal.cx>
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Subject: Re: [musl] [BUG] sysconf implementing _SC_NPROCESSORS_(CONF|ONLN)
 incorrectly

On Tue, Apr 14, 2020 at 12:08:52PM +0200, Florian Weimer wrote:
> * Rich Felker:
> 
> >> For glibc, we had to change our logic to artificially inflate the CPU
> >> to 2 if we cannot determine it, as the more conservative choice.
> >
> > Wait, you mean some software is abusing these interfaces to omit
> > memory barriers or something? *facepalm* *sigh*
> 
> Yes, indeed.  glibc itself parses uname -v output for this purpose
> (something we should probably remove, too).

I don't understand. Certainly it's not executing a child process at
runtime. Do you mean SYS_uname or are you talking about guessing
number of cpus for parallel build at make time or something?

Rich